Cocos Island in the East Pacific is the largest uninhabited island in the world, it’s remote, wild and and excellent diving location. Cocos is located 300+ miles south-southwest of Costa Rica, accessible only by boat. The area is dived only by liveaboard and there are no places to stay on the island. You likely see hordes of hammerhead sharks and dense populations of pelagic and reef fish, turtles, many types of eels, starfish and even a rare frogfish. Here, on Cocos, the fish population has been allowed to grow in harmony with the natural balance of the food chain, which is why such a great diversity and quantity of sea life is prevalent. It’s probably the best place in the world to go diving with sharks. Absolutely no problem with crowds of other divers and all the lliveaboards are excellent.
Best Dive Destinations in Cocos Island
Alcyone
At a depth of 150ft (46m), this roundish mound of barren rock looms up from the sandy bottom, creating an eerie feeling. The highest point is at a depth of 80ft (25m). It is home to the largest and most seen hammerhead shark schools in Cocos.
Dirty Rock
Every kind of marine species affiliated with the Cocos area seems to be attracted to this rock.
Submerged Rock
Underwater, this rock plunges down both sharply and gradually. It is broken up with large ledges, some with sandy bottoms, and an outer pinnacle. The colorful, prolific fish life gives relief to the harsh contours of the reef. Sometimes the fish gather in such numbers that they momentarily blot out the sun.
Sharkfin Rock
During a dive, it is quite possible to go around the entire rock. The island side harbors whitetip sharks and marble rays, at times, lying on the sand. The jack schools tends to congregate on the outer side, where there is often some current.
Dos Amigos Grande
Cocos offers many thrilling dives but this is the most spectacular underwater vista. As you near the end of the wall, an enormous deep archway will appear. The sun pours through from above, and schooling fish, suspended in the entrance, are shrouded in limestone. Inside this subaquatic cathedral the walls seem to come alive. Light dances off every surface and the mass of fish and sharks tease and tantalize the eye as well as the camera lens.
Small Dos Amigos
This, the other of the two islands, is similar in appearance above water to its brother, but not below. Here some large snappers are so huge that they make the whitetip sharks look insignificant.
Manuelita Outside (West)
Lurking among the boulders of this dive are moray eels, lobsters, turtles, and a variety of vividly colored fish, such as blue-stiped snappers, trumpetfish, squirrelfish and hawkfish. Whitetip and hammerhead sharks circle around above and below.
Manuelita Inside (East side)
This site offers a tremendous variety of fish: jacks, rainbow runners, milkfish, grunts, goatfish, snappers, parrot, butterfly, puffer, box fish and turtles to name a few.
Manta Ray Corner
There is a rock off this point where the constant choppy sea sends up clouds of spray on impact. Here, beneath the surge and churning sea, is a dive that offers a chance of manta ray encounters.
Marble Ray Point
So far, this is one of two places on Cocos Island where marble rays rest motionless on the bottom in a group. If approached correctly, they will allow a diver to get quite close. This is an ideal spot to study their behavior and take some pictures.
Chatham Bay
During the day, butterfly and damsel fish are a few of the fish that can be seen roaming the reef for food. This would certainly be a good snorkeling and night dive spot.
Wafer Bay
There is a tunnel or deep cave on the north side of the bay, set in the rock. It is visible above and below the water level, but strong surges make entry impossible. Reef life is sparse, although it is possible to see rays, eels and some fish.
When to Visit Cocos Island
Cocos Island lies in an Intertropical Convergence Zone. This zone is where the weather patterns of the two hemispheres converge near the equator. Here North and Southeast trade winds meet with the north and south equatorial currents. The warm north and south equatorial currents run in a westerly direction, which helps create a humid climate. While between the two, the counter equatorial current runs in the opposite direction. Ascending nutrient rich waters with these currents as they converge.
This high rainforest-clad island, with diverse currents and weather patterns, is rarely seen without some kind of cloud cover and receives 18-24ft (6-8m) of rain annually.
The dry season is from January-April, and the wet season is June-December. Torrential rain and beautiful sunny skies can be expected throughout the year.
Water temperatures are variable, but basically run between 74-87°F (23-30°C). Temperatures can vary dramatically with depth. Nearer the surface the water is warmer and deeper down it gets colder quickly. Air Temperatures range rarely fall below 75°F (20-33°C). It is hard to imagine good underwater visibility associated with an area of such high rainfall but, in fact, it has little effect.